Diesel vehicles today emit fewer pollutants than older vehicles, thanks to a zeolite catalytic converter that was invented around 10 years ago. Although many groups have investigated this catalyst since then, it was still unclear why it is so much more effective. By observing the catalyst’s interior in three dimensions at the nanoscale level, researchers from Utrecht University and Oak Ridge National Laboratory (ORNL) in the U.S. have now found the explanation. After simulating 217,000 km of wear, they compared a ‘new’ and an ‘old’ version of the catalyst in detail. This revealed the current catalyst retains much more of its ‘younger’ structure than previously used diesel catalysts. The researchers also found the underlying reasons that this catalyst is so much more stable over its lifespan, and experiences only minimal damage compared to previously used catalysts. The results are published today in Nature Communications.